Sunday, January 31, 2010

Mt. Rainier's melting glaciers create hazard

Sandi Doughton in the Los Angeles Times: The fallout from Mt. Rainier's shrinking glaciers is beginning to roll downhill, and nowhere is the impact more striking than on the volcano's west side. "This is it in spades," U.S. Park Service geologist Paul Kennard said recently, scrambling up a 10-foot-high mass of dirt and boulders bulldozed back just enough to clear the road.

As receding glaciers expose crumbly slopes, vast amounts of gravel and sediment are being sluiced into the rivers that flow from the region's tallest peak. Much of the material sweeps down in rain-driven slurries. "The rivers are filling up with stuff," Kennard said from his vantage point atop the pile. He pointed out ancient stands of fir and cedar now standing in water.

Inside Mt. Rainier National Park, gravel-choked rivers threaten to spill across roads, overtake bridges and flood the historic park complex at Longmire. Downstream, communities in King and Pierce counties cast a wary eye at the volcano. As glaciers continue to pull back, the result could be increased flood danger across the Puget Sound lowlands for decades.

"There is significant evidence that things are changing dramatically at Mt. Rainier," environmental consultant Tim Abbe said. "We need to start planning for it now."

Similar dynamics are playing out at all of the region's major glaciated peaks, according to research hydrologist Gordon Grant of the U.S. Forest Service. Climate experts blame global warming, triggered by emissions from industries and cars, for much of the ongoing retreat of glaciers worldwide. North Cascades National Park has lost half of its ice area in the last century. Mt. Rainier's glaciers have shrunk by more than a quarter….

Emmons Glacier at Mt Rainier (2007).jEmmons Glacier at Mt. Rainier in Washington, shot by Vayu, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0 License

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